A look at reasons for Israeli airstrikes in Syria

In this photo released by the Syrian official news agency SANA, Syrian Information Minister Omran al-Zoubi speaks during a press conference in Damascus, Syria, Sunday, May. 5, 2013. Al-Zoubi says the Israeli attack is evidence of the Jewish state's links with Islamic extremist groups trying to overthrow President Bashar Assad's regime. He added that Syria has the right and the duty "to defend its people by all available means." (AP Photo/SANA)
— AP

In this photo released by the Syrian official news agency SANA, Syrian Information Minister Omran al-Zoubi speaks during a press conference in Damascus, Syria, Sunday, May. 5, 2013. Al-Zoubi says the Israeli attack is evidence of the Jewish state's links with Islamic extremist groups trying to overthrow President Bashar Assad's regime. He added that Syria has the right and the duty "to defend its people by all available means." (AP Photo/SANA)
/ AP

Iran is the senior partner in the axis since it supports the Assad regime and Hezbollah with weapons, though it's not clear how much tactical sway is being exerted by Tehran.

Advisers from Iran's Revolutionary Guard are believed to have longtime roles in Hezbollah's militia forces and Assad's army - serving as both point men for Tehran's aid and liaisons with the ruling clerics in Tehran. Yet Iran also keeps a distance from the actual battlefield.

Gen. Masoud Jazayeri, assistant to the Iranian chief-of-staff, told Iran's state-run Arabic-language Al-Alam TV on Sunday that Tehran "will not allow the enemy (Israel) to harm the security of the region" and that "the resistance will retaliate against the Israeli aggression against Syria."

Iran would have a major say in any decision to retaliate for the airstrikes but is not believed to have an appetite for a confrontation with Israel. While Iran is fighting for regional influence and has often used its anti-Israel stance to do so, it has never attacked the Jewish state.

WILL THE ISRAELI STRIKES CHANGE THE COURSE OF SYRIA'S CIVIL WAR?

The uprising against Assad erupted in March 2011 and quickly evolved into a civil war, leaving tens of thousands dead and millions displaced. Assad and those trying to topple him remain locked in a battlefield stalemate, with neither side able to deliver a decisive blow.

The rebels are dominated by Syria's Sunni Muslim majority, while Assad is a member of the Alawite sect, an offshoot of Shiite Islam. He as rallied hardcore supporters around him, including members of Syria's ethnic and religious minorities who prefer the current regime to Sunni majority rule.

During four decades of rule, Assad and his father and predecessor, Hafez, used Syria's staunchly anti-Israel positions as a source of legitimacy even though both men kept Syria's frontier with the Jewish state quiet.

Syria's civil war has increasingly eroded Assad's anti-Israel "credentials," after the regime attacked Palestinian refugee camps in Syria and the Palestinian militant group Hamas, made up of Sunnis, broke with the regime because of its crackdown on the rebels.

If Assad does not retaliate for the latest Israeli strikes, his claims to anti-Israel militancy would become even more tenuous. In an attempt to deflect attention, Syrian government officials on Sunday tried to portray the Syrian opposition as engaged in a common cause with Israel.

Future Israeli air attacks could also wipe out key Syrian military installations. Rebel forces have managed to seize a number of Syrian military bases, seizing heavier weapons but have advanced only slowly because of the regime's air superiority.